It was narrated from Abu Sa'eed that the Prophet (ﷺ) said:
"When any one of you a wants to return (to have intercourse again), let him perform Wudu'." (RU)
English reference (RU): Vol. 1, Book 1, Hadith 263 (RU)
Arabic reference (RU): Book 1, Hadith 264 (RU)